Research Article

Detection of Salmonella enterica subsp. enterica via Quenching of Unincorporated Amplification Signal Reporters in Loop-Mediated Isothermal Amplification

Figure 7

Assay repeatability. Three different QUASR LAMP assays were done by the same operator over three days using samples in triplicate. Sample (2.5 μL) was added to 10 μL reagent mix then incubated at 65°C for 60 minutes, 80°C for 2 minutes, and cooled to 4°C for 10 minutes using two machines: (a) T100 Thermal Cycler (S/N 621BR14432; Bio-Rad Laboratories, Inc., CA, USA) and (b) Lab-in-a-Mug 2.0 Dry Bath Incubator (Manila HealthTek, Inc., Marikina, Philippines). Samples used were the No Template Control (NTC), Salmonella enterica subsp. enterica serovar Typhi DNA (STY), and Positive Control (PC; 106 copies/μL). Results were viewed using the EasyView™ LED Transilluminator (Manila HealthTek, Inc., Marikina, Philippines) which has a blue LED light and yellow plastic gel filter, and through agarose gel electrophoresis (1.5% agarose, 135 V for 25 minutes). Salmonella enterica subsp. enterica positives appear bright yellow green. All images were taken using a Canon EOS 750D camera. Interpretation of results are as follows: (+)–Positive using the LED transilluminator and positive in 1.5% AGE; (−) – Negative using the LED transilluminator and negative in 1.5% AGE.
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